Steam crimping of yarn

ABSTRACT

An apparatus and method for uniformly crimping yarn by passing a yarn through a confined crimping zone and providing means in the crimping zone for interrupting the flow of steam streams against opposed sides of the yarn. Each steam stream intermittently contacts the yarn at uniformly spaced portions along the length of the yarn with one steam stream contacting the yarn at a medial location between the contacting locations of the other steam stream. The yarn is thereafter cooled and recovered in a relaxed condition.

United States Patent Schmick Feb. 22, 1972 [54] STEAM CRIMPING OF YARN[72] Inventor: Hayes J. Schmick, Morrisville, NC.

[73] Assignee: Phillips Fibers Corporation [22] Filed: Sept. 29, 1970[21] Appl. No.: 76,433

[52] U.S. Cl ..28/l.4, 28/7212 [51] Int. Cl. ..D02g 1/16 [58] FieldotSearch ..28/l.2,1.3,1.4, 72.1, 72.11, 28/7212; 57/34 B, 157 F [56]References Cited UNITED STATES PATENTS 3,052,009 9/1962 Epstein et al...28/ 1.2 3,409,956 11/1968 Longbottom et a1. ..28/1.3

3,501,819 3/1970 Satterwhite ..28/1.3 3,525,134 8/1970 Coon ..28/1.4

Primary Examiner-Louis K. Rimrodt Attorney-Young and Quigg [57] ABSTRACTAn apparatus and method for uniformly crimping yarn by passing a yarnthrough a confined crimping zone and providing means in the crimpingzone for interrupting the flow of steam streams against opposed sides ofthe yarn. Each steam stream intermittently contacts the yarn atuniformly spaced portions along the length of the yarn with one steamstream contacting the yarn at a medial location between the contactinglocations of the other steam stream. The yarn is thereafter cooled andrecovered in a relaxed condition.

9 Claims, 3 Drawing Figures Pmlinrteza I812 3.643.298

INVENTOR.

H. J. SCHMICK F/G. 3 BY q"-"1* Q a? A T TORNEVS STEAM CRIMPING F YARN Inthe crimping of yarn by heretofore-utilized methods and apparatus, thecrimped yarn often is of a generally low quality owing to the variationsin the crimp along the length of the yarn and partial fracturing ofportions of the yarn.

Gear crimpers and stuffer box crimpers previously gave a crimp withuniform frequency and amplitude, but these methods are too slow to beeconomical. My invention produces the frequency and amplitude uniformityof the gear crimper without physical contact of the yarn and the gears,thereby eliminating bruising and breakage of the yarn whilesimultaneously operating at the speed of jet crimpers.

This invention therefore resides in an apparatus and method foruniformly crimping yarn without fracturing the yarn by crimping the yarnwith opposed jet steam streams and recovering the yarn in a relaxedposition. The jet steam streams are caused to impinge upon the yarnpassing through a crimping zone at uniformly spaced-apart locationsalong the length of the yarn by providing means for interrupting theflow of the steam streams. The means for interrupting steam flow iscontrolled to cause one steam stream to contact the yarn at a mediallocation between the contacting locations of the other steam streamthereby uniformly crimping the yarn in frequency and amplitude.

Other aspects, objects, and advantages of the present invention willbecome apparent from a study of the disclosure, the appended claims, andthe drawing.

The drawings are diagrammatic views of the apparatus of this invention.

FIG. 1 shows a frontal view of the apparatus of this invention withportions cut away,

FIG. 2 shows a plan view of the apparatus of FIG. 1 with portions of theapparatus cutaway, and

FIG. 3 shows a portion of another embodiment of an interrupting element.

Referring to FIG. 1, a yarn 2 is delivered at a substantial uniformspeed by delivering means 4 to a confined crimping zone 6. The yarn canbe of any synthetic material that can be crimped by contacting yarn 2with heat and a lateral force. Examples of yarn that can be crimped bythe method and apparatus of this invention are: polypropylene, nylon,polyethylene terephthalate, polyvinyl chloride, and the like.

The delivery means 4 can be a fluid-operated jet which forwards the yarn2 into crimping zone 6 of housing 1. The jet 4 is operated by a hotfluid such as steam from line 3 thereby preheating the yarn as it entersthe housing 1. Details of construction of such jets for forwarding yarnare known in the art. It is important, however, that the rate at whichyarn passes through the crimping zone 6 be substantially uniform inorder to uniformly crimp the yarn over the entire length. The yarn canbe fed to the delivery means 4 from a yarn-spinning assembly, drawrolls, a yarn package, or other process apparatus.

As shown in FIG. 2, first and second jet nozzles 12, 14 are located inthe crimping zone 6 on opposed sides of the yarn 2 passing through thecrimping zone 6 from the delivery means 4. An outlet end 16,18 of eachnozzle 12,14 is directed toward the yarn 2 and preferably one nozzle isspaced along the yarn a distance from the other nozzle in order to moreeasily provide for uniform operation of the apparatus at high speeds. Areservoir is connected to each of the nozzles 12,14 for the passage of astream of heated fluid, preferably steam, from the reservoir 20 andthrough each jet nozzle 12,14.

A controlling means 22 is associated with each steam stream forintermittently discharging steam from each nozzle 12 and 14 onto theyarn 2 at uniformly spaced-apart locations along the length of the yarn2 during passage of the yarn 2 through the crimping zone 6. Thecontrolling means 22 provides for discharging steam against the yarnfrom one of the nozzles, for example, the second nozzle 14, at locationson the yarn uniformly spaced between locations on the yarn 2 contactedby steam discharging from the opposed nozzle, for example the firstnozzle 12. A means such as a tube 24 or other apparatus known in the artis thereafter positioned in the pathway of the yarn discharging from thecrimping zone 6 for recovering and cooling the yarn in a substantiallyrelaxed condition by, for example, forming a yarn plug in the tube 24.That tube 24 can extend between the elements 26,28 to a positionadjacent nozzle outlet end 18, as shown in FIG. 1, for assuring the flowof yarn into the tube 24. Housing 1 is substantially closed except forthe openings of delivery and discharge of yarn 2 and is therefore underslight pressure due to the influx of steam a portion of which isexhausted through line 5 which can be controlled by means not shown.

A preferred embodiment of the controlling means 22 of the apparatus ofthis invention comprises first and second interrupting elements 26,28.Each element 26,28 preferably has a disclike configuration and iscoaxially positioned relative to the other element. The elements 26,28can be independently synchronously rotated about their axes butpreferably are fixedly attached one to the other, or are of unitaryconstruction. The elements 26,28 are positioned in the crimping zone 6with each element extending between the yarn 2 and each elementsassociated jet nozzle. Each element 26,28 has a plurality ofspaced-apart openings 30 extending therethrough in a direction towardthe yarn 2 with each opening 30 of each element 26,28 being ofsubstantially uniform configuration, spaced a common radial distancefrom; the common axis and spaced apart a common circumferentialdistance. Openings 30 and nozzles 12 and 14 are preferably orientedabout 45 toward the direction of travel of the yam 2 through theapparatus for providing a gentle forwarding of the yarn against the yarnplug. Each element 26,28 is preferably maintained on the axis at arotated position relative one to the other such that an opening of oneelement, for example element 26, is opposite a location on an equalcircumferential distance between adjacent openings of the other element:28. All openings 30 of the first and second elements 26,28 are rotatableat a uniform peripheral speed to a common elevation of the yarn 2 andthe associated nozzles 12,14 by a power means 32 such as a constantspeed electric motor, for example.

In order to uniformly crimp the yarn 2 to form a sinusoidal crimpconfiguration, it is preferred that the elements 26,28 be rotated by thepower means 32 at a uniform peripheral speed that is substantially equalto the lineal speed of the yarn entering the crimping zone 6. Dependingupon yarn delivery speed, the openings 30 through each element arecircumferentially positioned so that the rotational speed of theelements produces the sinusoidal period desired for the resultant yarn.

FIG. 3 shows another embodiment of the elements 26,28 wherein theelements have slots 31 formed therethrough and extending inwardly fromthe outer periphery of each element thereby forming the openings for thepassage of the steam streams from nozzles 12,14. These slots can be ofV, rectangular, or other configuration for forming a crimp in the yarnwhich has a configuration desired by the operator. It can also be seenthat the placement of the openings, relative to the yarn and element'sspeed, etc., can be varied to alter the configuration of the resultantcrimped yarn.

In order to further control the uniformity of the crimp of the resultantyarn, the first and second nozzles 12,14 each can have an openingextending therethrough that is of a common configuration and area andthe nozzles can each be connected to the reservoir 20 by a separate line34,36 having a common inside diameter and being of substantially equallengths for discharging a stream of steam from each nozzle with eachstream having a substantially equal velocity and temperature. Where saidlines and nozzles differ to a large degree, the force and temperature ofthe steam stream from one nozzle can crimp one portion of the yarn anoticeable amount more than the crimp caused by the other stream. Itwould, however, require relatively large stream variations to producevisible yarn crimp variations.

In the method of this invention, a preheated yarn 2 is uniformly crimpedduring passage of the yarn 2 through the crimping zone 6 at asubstantially uniform speed. In the crimping zone 6 a first jet streamof steam is uniformly, intermittently impinged upon one side of the yarnand a second jet stream of steam is uniformly, intermittently impingedupon an opposed side of the yarn 2 at locations on the yarn uniformlyspaced between locations on the yarn contacted by the first jet steamstream. The first and second jet steam streams have substantially equalvelocities and temperatures. The temperature of each steam stream ismaintained sufficiently high to plasticize the yarn in the crimping zoneand the velocity of each steam stream is maintained sufficiently high tocrimp the yarn in the crimping zone. After contacting the yarn with thefirst and second steam streams the yarn is cooled and recovered from thecrimping zone in a substantially relaxed condition for maintaining theimparted crimp. By controlling the steam streams, the yarn can becrimped to form a substantially sinusoidal configuration.

This apparatus can be used, for example, for crimping nylon 66 yarn withsuperheated steam operating at about 130 C., polyethylene terephthalatewith steam at about l65l75 C., and polypropylene with steam at about 1l-l C., at yarn speeds of about 800 meters/minute, and steam pressurepreferably in the range from about 50 to 150 p.s.i.g.

Other modifications and alterations of this invention will becomeapparent to those skilled in the art from the foregoing discussion,example, and accompanying drawing, and it should be understood that thisinvention is not to be unduly limited thereto.

What is claimed is:

l. A method for uniformly crimping yarn, comprising:

passing a preheated yarn through a confined crimping zone at asubstantially uniform speed;

uniformly, intermittently impinging in the crimping zone a first jetstream of heated fluid against one side of the yarn;

uniformly, intermittently impinging in the crimping zone a second jetstream of heated fluid against an opposed side of the yarn at locationson the yarn uniformly spaced between locations on the yarn contacted bythe first jet stream, said first and second jet streams of heated fluidhaving substantially equal velocities and temperatures with saidtemperatures being sufficiently high to plasticize the yarn in thecrimping zone and said velocities being sufficiently high to crimp theyarn in the crimping zone; and

cooling and recovering the yarn from the crimping zone in asubstantially relaxed condition.

2. A method, as set forth in claim 1, including controlling the heatedfluid streams for crimping the yarn in a substantially sinusoidalconfiguration.

3. An apparatus for uniformly crimping yarn, comprising:

a substantially closed housing having a fluid jet;

means for preheating and delivering yarn at a substantially uniformspeed to a hereafter crimping zone;

first and second jet nozzles located in the crimping zone on opposedsides of the yarn passing through the crimping zone with an outlet ofeach nozzle being directed toward the yarn;

means for passing a heated fluid through the nozzles;

controlling means for intermittently discharging the heated fluid fromeach nozzle onto the yarn at uniformly spacedapart locations along thelength of the yarn with one of the nozzles discharging the fluid againstthe yarn at locations on the yarn uniformly spaced between locations onthe yarn contacted by fluid discharged from the other nozzle; and

means for recovering the yarn from the crimping zone in a substantiallyrelaxed condition.

4. An apparatus, as set forth in claim 3, wherein the controlling meanscomprises first and second interrupting elements each having a coaxialconfiguration and being rotatably mounted in the crimping zone with eachelement extending between the yarn and its associated nozzles, eachelement having a plurality of spaced-apart openings extendingtherethrough with each opening of each element being of substantiallyuniform configuration, spaced a common radial distance from the commonaxis and spaced apart a common circumferential distance and each elementbeing maintained on the axis at a relative rotated position one from theother such that an opening of one element is opposite a location anequal circumferential distance between adjacent openings of the otherelement with all elements being rotatable to a common elevation of theyarn and that elements associated nozzle, and

power means for rotating the elements at a uniform peripheral speed.

5. An apparatus, as set forth in claim 4, wherein the power meansrotates the elements at a uniform peripheral speed that is substantiallyequal to the lineal speed of the yarn entering the crimping zone.

6. An apparatus, as set forth in claim 4, wherein the interruptingelements have slots extending inwardly from the outer periphery of eachelement thereby forming the openings of the elements.

7. An apparatus, as set forth in claim 4, wherein the first and secondnozzles each have an opening that is of common configuration and areaand the nozzles are each connected to a steam reservoir by a separateline having common inside diameters and substantially equal length fordischarging a stream of steam from each nozzle with each stream having asubstantially equal velocity and temperature.

8. An apparatus, as set forth in claim 3, wherein the first and secondjet nozzles are spaced along the yarn a distance one from the other.

9. An apparatus, as set forth in claim 4, wherein the spacedapartelement openings and their associated nozzles are oriented about 45toward the direction of travel of the yarn.

1. A method for uniformly crimping yarn, comprising: passing a preheatedyarn through a confined crimping zone at a substantially uniform speed;uniformly, intermittently impinging in the crimping zone a first jetstream of heated fluid against one side of the yarn; uniformly,intermittently impinging in the crimping zone a second jet stream ofheated fluid against an opposed side of the yarn at locations on theyarn uniformly spaced between locations on the yarn contacted by thefirst jet stream, said first and second jet streams of heated fluidhaving substantially equal velocities and temperatures with saidtemperatures being sufficiently high to plasticize the yarn in thecrimping zone and said velocities being sufficiently high to crimp theyarn in the crimping zone; and cooling and recovering the yarn from thecrimping zone in a substantially relaxed condition.
 2. A method, as setforth in Claim 1, including controlling the heated fluid streams forcrimping the yarn in a substantially sinusoidal configuration.
 3. Anapparatus for uniformly crimping yarn, comprising: a substantiallyclosed housing having a fluid jet; means for preheating and deliveringyarn at a substantially uniform speed to a hereafter crimping zone;first and second jet nozzles located in the crimping zone on opposedsides of the yarn passing through the crimping zone with an outlet ofeach nozzle being directed toward the yarn; means for passing a heatedfluid through the nozzles; controlling means for intermittentlydischarging the heated fluid from each nozzle onto the yarn at uniformlyspaced-apart locations along the length of the yarn with one of thenozzles discharging the fluid against the yarn at locations on the yarnuniformly spaced between locations on the yarn contacted by fluiddischarged from the other nozzle; and means for recovering the yarn fromthe crimping zone in a substantially relaxed condition.
 4. An apparatus,as set forth in claim 3, wherein the controlling means comprises firstand second interrupting elements each having a coaxial configuration andbeing rotatably mounted in the crimping zone with each element extendingbetween the yarn and its associated nozzles, each element having aplurality of spaced-apart openings extending therethrough with eachopening of each element being of substantially uniform configuration,spaced a common radial distance from the common axis and spaced apart acommon circumferential distance and each element being maintained on theaxis at a relative rotated position one from the other such that anopening of one element is opposite a location an equal circumferentialdistance between adjacent openings of the other element with allelements being rotatable to a common elevation of the yarn and thatelement''s associated nozzle, and power means for rotating the elementsat a uniform peripheral speed.
 5. An apparatus, as set forth in claim 4,wherein the power means rotates the elements at a uniform peripheralspeed that is substantially equal to the lineal speed of the yarnentering the crimping zone.
 6. An apparatus, as set forth in claim 4,wherein the interrupting elements have slots extending inwardly from theouter periphery of each element thereby forming the openings of theelements.
 7. An apparatus, as set forth in claim 4, wherein the firstand second nozzles each have an opening that is of common configurationand area and the nozzles are each connected to a steam reservoir by aseparate line having common inside diameters and substantially equallength for discharging a stream of steam from each nozzle with eachstream having a substantially equal velocity and temperature.
 8. Anapparatus, as set forth in claim 3, wherein the first and second jetnozzles are spaced along the yarn a distance one from the other.
 9. Anapparatus, as set forth in claim 4, wherein the spaced-apart elementopenings and their associated nozzles are oriented about 45* toward thedirection of travel of the yarn.